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Great Lakes Water Level Data

This page contains monthly mean lakewide water levels (from 1918 to present) including long-term averages, maximums minimums, and monthly means. It also includes daily Great Lakes water levels and real-time gage data for connecting channels water levels. 

Daily Great Lakes Water Levels

Daily Great Lakes Water Levels


Download .PDF (Imperial)

Monthly Mean Great Lakes Water Levels

Monthly Mean Lakewide-Average Water Levels

Monthly-Mean Lakewide-Average Water Levels


Download .CSV (Imperial)
Download .CSV (Metric)

Long-Term Maximum, Average and Minimum Water Levels

Monthly Mean Water Levels


Download .PDF (Imperial)
Monthly Mean Water Levels


Download .PDF (Metric)

Explore Great Lakes Water Management

All Great Lakes Water Management data contained herein is preliminary in nature and therefore subject to change. The data is for general information purposes ONLY and SHALL NOT be used in technical applications such as, but not limited to, studies or designs. All critical data should be obtained from and verified by the United States Army Corps of Engineers Detroit District, Engineering and Construction Division, Hydraulics and Hydrology Branch, 477 Michigan Avenue, Detroit, MI 48226. The United States of America assumes no liability for the completeness or accuracy of the data contained herein and any use of such data inconsistent with this disclaimer shall be solely at the risk of the user.

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